The present invention relates to a liquid feeding system for a humidifier.
Humidifiers in a breathing circuit for a patient are known. In such systems, a sterile liquid is placed in the humidifier with the liquid being heated, and an air mixture is passed from a ventilator through the liquid in order to heat and humidify the air mixture, and the resulting air mixture is passed to the patient. However, during use of the humidifier the liquid is utilized to humidify the air mixture, and it is necessary to periodically replenish the liquid in the humidifier. In the past, the humidifier was normally taken apart, and additional liquid was poured into the humidifier. It has been found that this procedure is inconvenient, and poses the possibility of contaminating the liquid due to handling of the liquid. Other procedures are to pour water through one of the ports of a cap for the humidifier. Alternatively, water can be fed from a suspended flexible solution bag through a special set. The disposable set, which is manufactured by a company, consists of a tee adapter which fits over the cascade outlet. The patient hose is connected to the perpendicular leg of the tee and the remaining leg is connected to the solution bag via a vinyl tube. Water is delivered through the adapter to the cascade by opening a tube clamp when required. Although the filling process is simplified it is still manual requiring frequent attention. Further, versions of the humidifier offer a special port for inserting a water feed system. The system, manufactured by a company, is composed of a suspended glass bottle which feeds the water through a large bore tube to a valve assembly which is positioned within the cannister. The valve is automatically closed when the water level reaches the required height. Although the system continuously feeds water as needed, the set-up must be cleaned and sterilized for re-use.